In the processing of thin substrates with a thickness of less than 1 mm, for example of wafers or in the production of silicon-based photovoltaic cells, the substrates which generally have a diameter of at least 20 cm (for example in wafer processing) and/or at least 10 cm diameter for noncircular, flat substrates (for example in Si-based photovoltaic cell production), are conventionally transported with vacuum grippers by robots between individual process modules. During gripping, also due to the applied vacuum, damage or breaking of the substrates repeatedly occurs, for very thin substrates even warpage on the suction holes of the vacuum grippers.
Existing approaches support the thin substrates by applying the thin substrates to carrier substrates (temporary bonding), therefore by temporary fixing on the carrier so that the thin substrates can be safely transported and processed in substrate processing systems. This method is currently not being used in the photovoltaics industry since it is too expensive compared to the market prices for these modules. Still, it is desirable to be able to use thin substrates since they enable higher efficiency in the conversion of light into electrical energy. In particular, semiconductor base material can also be saved if more preferably a corresponding production method for thin substrates is used in substrate production.
The major barriers to commercial use are moreover transport logistics or the type of transport as well as the technology in the production environment and the lack of suitable methods and means for transporting these thin substrates for example from the substrate manufacturer to photovoltaic production.